Multiprogram projector



Jan. 6, 1948. R. c. ENGELKEN 2,434,200

MULT IPROGRAM PROJECTOR Filed Feb. -23, 194A 9 Sheets-Sheet 2 FIG. 3.

i RICHARD c. ENGEL KEN, 01560 By MARY A. CNGEL KEN, EXECUTRIX INV ENT OR Jan. 6, 1948. R. c. ENGELKEN 2,434,200

MULTIPROGRAM PROJECTOR Filed Feb. 23, 1944 9 Sheets-Sheet 3 RICHARD c. ENGELKEN, pfcb By MARYA. ENGELKEN, :xm/m/x INVENTOR W y; 'ATTORN/YS 9 Sheets-Sheet 4 IJS.

INVE W N 6am Jan. 6, 1948. R. c. ENGELKEN MULTIPROGRAM PROJECTOR Filed Feb. 23, 1944 MARYAENGELKL'N, Exzcurmx RICHARD C. ENGELKEN; DEC'D BY W ATI'O YS W I i xbllll Filed Feb. 23, 1944 9 Sheetsheet 5 I IIIIIIII-l RICHARD C. ENGELKEN, DECD KEN,

B MARY A. ENGfL mumx mvzmvx Jan. 6, 1948. R. c. ENGELK-EN 2,434,200

MULT IPROGRAM PROJECTOR Filed Feb. 23, 1944 9 Sheets-Sheet 6 [I F FIGJO. 70

RICHARD C. ENGELKEN, DECD By MARY/1. L'NGELKEN, BYECUMIX INVENT OR Jan. 6, 1948. c, ENGI-ELKEN 2,434,200

MULTIPROGRAM PROJECTOR Filed Feb. 23, 1944 9 Sheets-Sheet 8 239 FIG. 20. W

261 241 In [I 292 [1681! l 287 4 23 8 zt ea 309 310 234 LS4 235% O RICHARD C. ENGELKEM DECD 236 B MARY A. fNGELKEN, L'xramwr INVENTOR BY gum Patented Jan. 6, 1948 UNITED STATES PATENT OFFICE MULTIPROGRAM PROJECTOR Richard C. Engelken, deceased, late of Clifton, N. J., by Mary A. Engelken, executrix, Clifton,

Application February 23, 1944, Serial No. 523,508

49 Claims. 1

The present invention relates to a multiprogram projector and more particularly to a selective automatic sound-on-film projector for reproducing any on of several film programs.

Although automatic and selective projectors of the juke box type are known, they are all impractical or unsatisfactory for one or more reasons. Also, such known projectors are extremely complicated and thus not capable of proper operation over a period of time without extensive maintenance or attention. Heretofore automatic multi-prcgram projectors have required a mechanical connection between the film handling units on the movable carriage and the film advancing means on the frame of the machine and such connection may introduce such displacements as to cause framing difficulties and considerable wea'r upon the inter-engaging parts.

The primary object of the present invention is the provision of a selective automatic multiprogram projector comprising a simple and practical film handling unit on a movable carriage, and effective and rugged carriage operating means for indexing the same, and a film advancing assembly including a member for engaging and moving the film program or film strip in the film handling unit.

Another object of the invention is the provision in each of the plurality of film handling units of an optical compensator operatively connected to the film program which in turn is moved by the film engaging member of a film advancing assembly.

A further object of the invention is the provision of a carriage operating means for moving the plurality of film handling units with simple harmonic motion and timed so that the carriage comes to rest as each film program is in al gnment or in juxtaposition to the optical system or reproducing means of the projector.

Still another object of the invention is the provision of a film handling unit comprising a mounting member for detachable connection to the movable carriage and a plurality of film engaging rollers, certain of said rollers being movable and biased for cooperation with the film program as it is engaged and disengaged by the film advancing assembly.

A still further object of the invention is the provision of film handling units adapted to contain a film strip carrying a pair of picture series and a pair of corresponding sound tracks and including one or more optical elements adapted to co-operate with other optical elements on the frame of the projector.

Another object of the invention is the provision in each of said film handling units of an optical compensator comprising a rotatable optical flat mounted for rotation in the mounting member of said unit.

A further object of the invention is the provision of a carriage operating means for engaging and moving the carriage with simple harmonic motion and for moving each film program or each picture series and sound track into juxtaposition with respect to an optical system on the projector and comprising a biased notched bar on the carriage engaged and moved by a p n on a rotating arm, said notches and rotating pin being arranged so that the carriage and film handling units are moved with simple harmonic motion and the film programs are in alignment or juxtaposition with respect to the opticalisystem during the rest periods of the simple harmonic carriage operating means.

Still another object of the invention is the cooperation between the biased slotted bar on the carriage and a pair of rotatable pins of the carriage operating means so that the biased bar causes accurate positioning of the carriage as each film program is aligned with the optical system.

A still further object of the invention is the provision of a film advancing assembly mounted upon a movable support and biased by gravity toward one posit on. Another object of the invention is a film advancing assembly including a rotatable drum, a driving means and a fiywheel pulley all arranged upon a movable support so that the center of gravity of the advancing assembly causes movement thereof into an operative position.

A further object of the invention is the provision on the film advancing assembly of a projection control member, a protective control member and/or parts of a sound reproducing system.

Another object of the invention is the provision of an assembly moving means for moving the film advancing assembly with respect to said movable carriage and the film handling units thereon.

Other and further objects of the invention will be suggested to those skilled in the art by the description which follows.

The above-mentioned and other objects of the invention are embodied in a multi-program sound-on-film photographic projector comprising a frame, an optical system thereon, a sound reproducing means including a photo-electric cell on said frame, a carriage means supporting a plurality of film handling units each adapted to contain a perforated endless film strip bearing a pair of laterally adjacent image series and sound tracks associated therewith and arranged within said unit with two film strip portions in laterally overlapping relation, an optical conductor angularly arranged in each unit and for directing the image in the sound tracks from one'film portion to one side of the laterally overlapping film portions, a bar on said carriage means and provided with a plurality of notches each corresponding in number and location to the number and location of said image series on said carriage means, an optical compensating means mounted on each of said film handling units and operatively connected to the perforated film strip therein, a carriage operating means operatively engaging the notches in said bar and for moving said carriage means with simple harmonic motion, a film advancing assembly including a movable support, a drum rotatably mounted thereon and a driving means on said support, said support, drum and driving means being so arran ed and located that said drum is moved by gravity into frictional engagement with a selected film program, an assembly moving means operatively connected to said support and for moving said film assembly and drum against the gravitational action and moving said drum out of engagement with a. film program and away from its film handling unit. a film operated control means mounted on the support of said film advancing assembly and for engaging the film strip when said drum is moved into engagement therewith, and a light source and associated sound optical member both mounted on said support and movable into alignment with a sound track on said film strip when said drum is moved into engagement therewith and for directing a li ht beam through a sound track overhanging said drum and through said optical conductor in said film handling unit onto said photoelectric cell on said frame. Obviously. the aforementioned means and elements not only combine to produce the complete combination described but said elements also co-operate two or more at a time to produce other comb nations or sub-combinations which are contemplated by the invention and claimed hereinafter. Certain of the combinations, such as combinations between the carriage and carria e operating means may be quite independent of the film adva cing means and conversely the novel features of the film advancing means may be independent of the carria e and carriage o erating means and mav be advan ageously emplo ed on other than multiprogram projectors. Thus. the present inv ntion is not to be imited by the i lustrated embodiment thereof but has a scope as broad as interpretation of the cla ms permits.

Reference is hereby made to the accompanying drawings wh rein similar re erence characters des gnate simi ar element and wherein:

Fi 1 is a front elevation of a sui ab e cab net for 'he multi-program projector of the in ention.

Fig. 2 is a vertical section taken on the line 22 of Fig. 1 and including an end view of the mul i-program projec or mechanism.

Fig. 3 is a vertical transverse section through the multi-progra-m projector of the invention.

Fig. 4 is a fragmentary front elevation of the I projector mechanism as viewed from the rear of Figs. 6 and '7 are fragmentary front elevations of the notched bar on the carriage means and constituting a part of the carriage operating means, Fig. 7 illustrating the change in position of the notched bar after rotation of the rotatable indexing arm.

Fig. 8 is an enlarged fragmentary vertical section through the optical axis of the projector and showing particularly the operation of the carriage operating means and location of various elements on the movable film advancing assembly.

Fig, 9 is a rear elevation of a film handling unit and showing the arrangement of guide rollers and sprockets therein.

Fig. 10 is an enlarged front elevation of a portion of the film strip carrying two series of picture images and two corresponding sound tracks.

Fig. 11 is a side elevation of the non-rewind coil and mounting assembly preferably located at the top of the film handling unit.

Fig. 12 is a fragmentary horizontal section through the sprocket of the film handling unit and taken on the line [2-12 of Fig. 9.

Fig.v 13 is a horizontal section through the optical compensator of the film handling unit taken on the line |3-| 3 of Fig. 9.

Fig. 14 is a horizontal fragmentary section through the film advancing assembly and a pair of film handling units and shows particularly the arrangement of the elements of the sound reproducing and optical system,

Figs. 15 and 16 are fragmentary horizontal sections through a portion of the film advancing assembly and film handling units and showing the two positions of the film operated switch member which is moved to said positions by relative positions of the film handling units and film advancing means and by notches in the edge of the film programs.

Fig. 17 is a fragmentary horizontal section through the film advancing assembly and a pair of film handling units and shows the co-operation of the protective control means with a film program.

Fig. 18 is a fragmentary side elevation of a portion of the film advancing assembly.

Fig. 19 is an end elevation of the film advancing assembly and the assembly moving means.

Fig, 20 is a wiring diagram showing the various control and operating circuits for the multi-program projector.

Fig. 21 is an operating diagram showing the relative movement, energization and/or operation of the various elements and circuits to produce the automatic operation contemplated by this invention.

Although the illustrated embodiment of the invention relates to a film strip bearing two series of motion p cture photographic images and laterally adjacent variable area sound tracks, it is to be understood that many features of the invention are not limied to a plurality of film programs on a single film strip. The term film program" as used herein refers either to a single series of picture images, a single sound track, or to a plurality of series of pictures and sound tracks or both. In other words, a multi-program projector according to the invention may be for pictures only or for sound only, or for both sound and picture programs. Although the multi-program projector is shown as being enclosed and facing the rear of the cabinet, the invention is not limited to enclosing of the multi-program projector or to any particular arrangement thereof within a cabinet or casing. The terms front and rear, except as expressly referred to the cabinet, are used herein with respect to the multi-program projector which is considered to face in the direction of propagation of the image or picture light beam therethrough.

Cabinet, frame and accessories According to the illustrated embodiment the multi-program projector is housed in a cabinet having a base 20, a front wall 2|, side walls 22, a rear wall 23 and a top 24. The image beam from the projector is preferably reflected by one or more mirrors onto a rear view projection screen 25 mounted within an aperture in the upper portion of front wall 2|. As shown, the projector may be directed toward the rear of the cabinet and mirrors 26, 2'1 and 28 are arranged therein, mirror 28 being mounted upon a bracket 29 on rear wall 23, to direct the image beam onto said screen 25. A loud speaker 30 and the amplifier 3| of the sound reproducing system may also be mounted upon the front wall 2| of the cabinet.

A plurality of manually operable devices or push buttons 32 are mounted across the front of the cabinet on wall 2| and are related in a known manner with a coin slot 33 also preferably on the front of the cabinet.

The projector proper is mounted within the cabinet upon a pair of cross beams 34 which are supported from the base 20 or side walls 22 thereof. A supporting plate 35 is fastened to cross beams 34 and extends toward the front of the cabinet to support a lamphouse 36 and a channel beam 3'! also extends toward the front of the cabinet for a purpose to be later described.

Th lamphouse 36 has a bracket 38 supporting a. socket 39 for a light source or incandescent lamp 40. A blower 4| is operated by a motor 42 and directs a blast of air upwardly through lamphouse 36 and through the perforated top thereof. A bracket 43 on the front wall of lamphouse 36 supports a photo-sensitive member or photo-electric cell 44. A condenser assembly 45 may be mounted in the front wall of lamphouse 36 or is located in any other suitable manner for directing a light beam onto the film in the projector gate.

End frames 46 are mounted at each end of the cross beams 34 and are fastened thereto by bolts 41. Each of said end frames has a bearing sleeve 48 in the lower portion thereof and each has an upper vertical face. A cross member 49 has a U-shaped cross section and has its ends f stened to the vertical faces of the end frames 46 by bolts 50. Said cross member 49 is provided with a square lens opening 5|, see Fi s. 3 and 4, and includes a collar 52 sup orted behind said opening 5| b angular supports 52', preferably integral with said member 49 and cellar 52, see Figs. 4, 5 and 8. The objective assembly 53 is mounted in said collar 52 in a'ignment with condenser assembl 45. has a rack element 54 and has a front element 55 extending th ough the opening 51 in cross member 49, see Figs. 3 and 8. A pair of parallel rails 56 and 51 are res ectively fa ened to the ends of cross member 49 by screws 58 and constitute the support for the carriage later to be described. An intermediate frame member 59 has its ends fastened to the cross beams 34 and is provided with a bearing sleeve 60.

The movable carriag The movable carriage, see Figs. 3, 5 and 8, comprises a pair of parallel members mounted for movement along the aforementioned parallel rails 56 and 51 of the frame. The lower carriage frame member 6| carries two pairs of rollers for laterally guiding said frame member 6|, one pair of rollers 62 being located at one end and another pair of rollers 63 being located at the other end of said carriage frame member 6|. Rollers 64 and 65 are mounted on said carriage frame member SI for rotation about horizontal axes and bear upon the top edge of rail 51. The upper carriage frame member 66 has rearwardly extending end arms 6! and carries a pair of rollers 68 for engaging opposite sides of the upper rail 56.

The film handling units The various film programs for the multi-program projector are provided in film handling units, see Figs. 3 and 8 to 17, inclusive, which are detachably mounted upon said carriage or carriage means. Said film handling units may have any suitable construction but that disclosed herein has many advantages and unique features. Such a film handling unit has side walls 69 and 10 which are maintained in spaced relation by posts H and by a mounting member '12. Said mounting member 12 preferably has fiat sides for abutting and attachment to the walls 69 and 1D and has a generally concavo-convex cross section. The ends of mounting member 12 are plane and are arranged for attachment to the carriage frame members GI and 66 by means of bolts 13. The convex surface of said mounting member 12 has a, film guiding recess or track 14 and the other side of said mounting member is provided with a concavity 15. Said mounting member 12 is provided with an aperture 16 having an enlarged portion 16' and extending from track 14 to concavity 15.

A non-rewind magazine is mounted upon the up er end of side wall 10 and comprises a plurality of radially arranged rollers 11 for engaging the edges of the film convo utions in a film coil 7 18 and a plurality of pairs of rollers 19 engaging the surface of the inner convolution of said film coil '18. An adjustable roll r also enga es the inner convolution of said film coil 18. Such nonrewind assembly is of known form and is adapted in the usual way to deliver a film strip F1 from the center of said film coil 18 and to take up a film strip F: onto the outer convo ution of said film coil 18. While the non-rewind film assembly may be operated in the op osite direction satisfactorily, it has been found that operation in the direction shown is pre erred.

The film s ri or film program is withdrawn from and delivered to coil 18 by means of a sprocket assemb y. best sh wn in Fig. 12. and comprising a shaft 8| journ led in ball bearings 82 in the res ec ive side walls 69 and 10 and a sprocket drum 83 having teeth 84 and fastened to said shaft 8 by a set screw 85 and a second sprocket drum 88 provided with peripheral recesses 81, having tee h 88 and fas ened to shaft 8| by a set screw 89. A ro ler 99 is rotatably mounted on a shaft 9' extending from side wall 0 and directs the film stri F1 onto s rocket 83 from whe ce the fi m strip F'i asses throu h the film guiding track 14 in mounting member 12 and ast the at a er ure 16. Other fixed id er rollers 9L 92. 93. 94, 95, 96 and 91 direct the film downwardly and u wardly in the film handling unit. A film roller 98 is mounted for rotation about a skew axis on an arm 99 having one end rotatably 7 mounted on the shaft I and also supporting the roller 93. A coil spring IOI has one end engaging a pin I02 on arm 99 and its other end engaging the side wall 69 so as to bias said arm 99 and roller 98 to move downwardly and tension the film strip within the film handling unit.

A second biased roller I03 is preferably covered with a friction material and is mounted upon a shaft I04 between a pair of arms I05 journaled on a shaft I06 extending between the side walls 69 and I0. A coil spring I0! has one end engaging a pin I 08 in one of arms I05 and its other end engaging one of posts II. The action of spring I01 holds the extension I09 of arm I05 against said post 1 I.

The side walls 69 and I0 are provided along one edge in the lower portion thereof with circular recess I I0 and which permit the entry of a film advancing member for driving engagement with the film strip and, in a manner to be explained, to move the film strip into a curved path. The function of biased roller 98 is to tension the film strip and draw the portion F1 thereof into a straight line between said rollers 92 and 93, see Fig. 8. The curved position of film strip F1 as caused by the film advancing member is shown by the broken line in Fig. 8 and it is apparent that the movement of the film into this curved path presses the same against the reaction roller I03 and so that the fim strip F1 is frictionally gripped between the film advancing member and said roller I03, as shown in Fig. 3.

The film strip moving downwardly within the film handling unit has been designated as F1 and the film strip moving upwardly has been designated as F2. The film path from the coil I8 is as follows: Over roller 90, sprocket drum 83 and in engagement with sprocket 84, through the film guiding track I4 in mounting member 12 and past aperture 16, around fixed rollers SI. 92 and 93, around the canted and movable roller 98 which laterally displaces the fi m strip now designated as F2, over rollers 94, 95, and 98. over sprocket drum 85 in engagement with sprocket 88 and over roller 91 to the outer peri hery of the coil 18. In the lower port on of the film handling unit the film strips F1 and F2 are in laterally overlapping reationship, see particularly Fig. 9.

The foregoing arrangement of the film handling unit is advantageous for many reasons among which is the accurate location of the mounting member (2 upon the carriage frame and with respect to the objective assembly 53 and particularly with respect to the back element 54 thereof which extends into the concavity T5 of the mounting member 12. This compact arrangement of the film gate and the film handling assembly and the ob ective assembly 53 in al gnment with the lamp 40 and condenser assembly 45 insures optimum projection results. particularly for image frames arranged in laterally adjacent series on the film strip.

The film strip F, see Fig. 10, is provided along one margin with perforations I I I, has a series of picture images I I2, a variable area sound track II3 adjacent thereto, a second series of picture images H4 and a second sound track II5 along the other margin thereof. Said film strip is also provided in a known manner with a structural variation at the conclusion of a picture and/or sound program thereon. Such structural variation may conveniently be provided as a notch I IS in the unperforated margin of the film, see Figs. 15 and 16.

Carriage operating means The carriage operating means, according to the present invention, is unique in several respects and particularly in imparting simple harmonic motion to the carriage means and timed so that there is a rest period or zero movement as each film program on the carriage is moved into alignment or juxtaposition with respect to the optical system and in providing an accurate locating arrangement for the carriage by reason of cooperation between the members of the carriage operating means.

Such simple harmonic carriage operating means comprises broadly a notched or slotted member on the carriage and a rotatable member on the frame for engaging said notches or slots for intermittent movement of the carriage. The notched or slotted member is best shown in Figs. 3 and 5 to 8, inclusive, and comprises a ,bar II'I movably mounted upon the carriage as by a pair of arms II8 pivotally connected to the end arms 61 of the carriage frame by shouldered screws IIS and attached to the bar II! by screws I20. The bar III extends beyond one of arms II8 as shown in Figs. 5, 6 and 7. Said bar I I! is biased to the position shown in Fig. 3 by springs I2I, see Fig. 8, attached at one end to the arms II8 by pins I22 and attached at the other end to pins I23 on the carriage frame or carriage frame member 0|. Notches I24, see Figs. 6 and '7, are provided along one edge of bar Ill and are each located to correspond to the position of a film program upon the carriage. In the illustrated embodiment there are four film handling units but since each unit carries two fi'.m programs there are eight notches in the bar I I1 each corresponding to a film program. An extra notch is placed at the extreme right end of bar II"! to perform the locating function to be explained hereinafter.

Actuation of the carriage and notched bar II! is accomplished by a rotatable member. As shown, such rotatable member comprises an arm I25, see Figs. 3 to 8, inclusive, mounted upon a shaft I28 journaled in a bracket I 21 which is fastened by screws I28 to the front of cross member 49, see Figs. 3, 4, 5 and 8. The arm I25, as best shown in Figs. 4, 5 and 8 has mounted on one end thereof a pin I29 and on the other end thereof a pin I30. The pin I29 is spaced from the axis of shaft I26 a greater distance than the pin I30 which is quite near the axis of shaft I26. However, the spacing between centers of said pins I29 and I30 is equal to the spacing between said notches I24. Rotation of shaft I26 may be accomplished in any known or suitable manner and according to the invention the carriage operating means is actuated by a motor I3I mounted on supporting plate 35 and having a pulley I32 and an endless belt I33 encircles said pulley I32 and a large diameter pulley I34 fastened to shaft I 26 and spaced from one bearing of bracket I21 by a collar I35. Energization or operation of the indexing or carriage operating motor I3I causes rotation of shaft I28, arm I25 and pins I29 and I30 thereon. Said motor I3I is of known form, is reversible in operation and is preferably a permanent magnet type of motor which stops immediately upon de-energization.

When said motor I3I rotates in one direction the arm I25 and pins I29 and I30 thereon are rotated, for instance, in a counter-clockwise direction as viewed in Figs. 4 and 6, the pin I29 engages one of the notches I24 and raises the bar H1 against the action of springs HI and simultaneously moves said bar H1 and the entire carriage and film handling units along rails 56 and 51 with simple harmonic motion. After 180 rotation of arm I25 and shaft I26 the pin I30 then engages the succeeding notch I24 to raise and move bar II1 and the carriage also with simple harmonic motion but moves the carriage a much shorter distance because of the shorter distance between the axes of shaft I26 and of the pin I30. Pin I29 is spaced from the axis of shaft I26 so that by 180 rotation thereof the bar H1 and the carriage means are moved to bring the nearer film program on the next film handling unit into juxtaposition with respect to the optical system and the spacing of pin I30 from the axis of shaft I26 is such that 180 rotation thereof in engagement with a notch I24 moves the bar I I1 and the carriage mean so as to bring the laterally adjacent picture series on the same film strip into alignment with the optical system. In other words, the carriage means is moved step by step successively to bring each picture series and/or sound track on a film strip into juxtaposition with respect to the picture and ound optics, each effective 180 rotation of pin I29 bringing another film handling unit into position and each effective rotation of the pin I30 bringing the other picture series and sound track of the same film into alignment.

Also, the notches I24 are arranged on bar II1 so that the disengagement of one pin and engagement of the other pin occurs when a picture series and/or sound track is in juxtaposition with the optical systems. When pins I29 and I30 are simultaneously within a pair of notches I24 the bias on bar II1 tends to hold said pins and the arm I25 in that position. In other words, the indexing motor I3I is de-energized at such time, in a. manner to be later described, and the action of spring I2I on bar II1 compels simultaaneous engagement of adjacent notches I24 with the pins I29 and I30 so as accurately to locate the carriage in such position. The extra notch in the right-hand end of bar I I1 is for the purpose of providing this locating function when the carriage is in position to align the extreme righthand film program with the optical system. Also, if there should be any overtravel by motor I3I, the bias on bar H1 and upon Din I29 or pin I30 returns the arm I25 to cause simultaneous engagement of said pins with the corresponding notches in the bar II1. Consequently, the carriage is accurately located in each position particularly when the indexing motor I3I is stopped.

Film advancing assembly The film advancing assembly is moved to an inoperative position during the aforementioned movement or indexing of the carriage and is moved to an operative position after the selected film program is in juxtaposition with respect to the optical systems. Also, the film advancing assembly is operative to move only the film program in juxtaposition and includes a rotatable member constituting the sole driving connection to the film strip to be moved. According to the present invention, the rotatable member of the film advancing assembly serves both as the film moving member and the sound drum of the sound reproducing system.

According to the illustrated embodiment, the film advancing assembly comprises a support including an arm I36, and a bell crank I31 both mounted upon a shaft I38 which is journaled at one end in the bearing sleeve 40 and of frame 46 and at the other end in the bearing sleeve 60 of the intermediate frame member 59, see Fig. 4. The bell crank I31 has an intermediate sleeve I39 fastened by pins I40 to shaft I30, has a horizontally extending arm I4I, see Figs. 3 and 18, carrying at its outer end a platform I42 having a depending flange I43 and has an upwardly extending arm I44 carrying on its upper end, see Fig. 4, a sleeve I45 in which a ball bearing I46 is mounted by means of a retainer ring I41 and screws I48. The arm I36, see Figs. 4 and 8, has a sleeve I49 fastened to shaft I38 by pins I50, has an upright extension I5I in which a set screw I52 for carrying a lock nut I53 is threaded, and has a lateral extension I54 supporting a bushing I55 in coaxial alignment with the ball bearing I46 on the upper end of arm I44 of the bell crank I31. A shaft I56 is journale'd in said ball bearing I46 and said bushing I55 and extends beyond the ball bearing I46, see Fig. 4, to receive a large diameter pulley I51 having a hub I58 and set screw I59 therein for attachment of pulley I51 to shaft I56. The other end of shaft I56 carries a drum I60 which is fastened to shaft I56 by a pin I6I and which has an internal annular recess I 62 rendering said drum I60 partially hollow for a purpose to be explained. Preferably, the periphery of drum I60 is covered with a suitable material for frictional engagement with the surface of a film strip.

A driving means, such as a film driving motor I63, is mounted upon the platform I42 at the outer end of arm I4I of bell crank I31. Said film driving motor I63 has a pulley I64 encircled by an endless belt I65 which also encircles the previously mentioned large diameter pulley I51 on the end of shaft I56. Said pulley I51 is of large diameter and has considerable inertia so that it acts as a flywheel to render the rotation of the sound drum I60 uniform in a manner well understood by those skilled in the art of reproducing sound-on-film.

The film advancing assembly is arranged so as to be biased toward one position by gravity. For this purpose, the film drive motor I63 is displaced a relatively large distance from the pivotal axis or shaft I38 of the assembly and the shaft I 56, large diameter pulley I51 thereon and arms I36 and I44 being substantially above the shaft I38 have a small effective displacement from the pivotal axis so that the center of gravity of the complete film advancing assembly is between shaft I30 and motor I63 and the normal tendency is for the film advancing assembly to swing about shaft I38 in a counter-clockwise direction as viewed from Figs. 3 and 8 and normally to move the drum I60 toward the carriage and film handling units thereon. As the film advancing assembly is moved toward its operative position, the periphery of drum I60 engages the film strip F1 which is stretched in a straight line between rollers 92 and 93, see Fig. 8, by reason of the bias or spring action of roller 98. Continued movement of the film advancing assembly toward its operative position curves said film strip F1, overcoming the action of spring operated roller 98 and moving a portion of the film strip F1 between said rollers 92 and 93, into engagement with the reaction roller I03 and into the position shown in dotted lines in Fig. 8 and in full lines in Fig. 3. Thus, the frictional engagement between drum I60 and the film strip is gradually increased, first by the action of roller 98 and finally by the frictional engagement of the film strip between reaction roller I03 and the sound drum I60. In its final position, the frictional drive from the sound drum I60 to the film strip is sufficient to move the film strip without any appreciable slipping. The recess H in the side walls 69 and of the film handling units are for the purpose of permitting entry of the shaft I56 of the film advancing means, see particularly Fig. 14. Also, said shaft I56 must have a length equal to or greater than the maximum carriage movement and so that the drum I60 may engage the most remote film strip or film program without interference between the large diameter pulley I51 and/or bell crank I31.

In the illustrated embodiment according to which laterally adjacent picture series or sound tracks are provided on the film strip, the drum I60 of the film advancing assembly enters each film handling unit in either of two positions depending on whether one or the other picture series and/or sound track is to be reproduced. For reasons which shall appear later, the sound track to be reproduced must overhang the end of drum I60 and consequently, when the sound track I I3 on the center of the film is to be reproduced. somewhat more than one-half of the film strip F overhangs the end of drum I60, as shown in Fig. 14. Nevertheless, the frictional engagement between the film strip and the portion of the periphery of sound drum I60 is sufiicient for movement of the film by the drum without appreciable slipping. In the other relative position of the film handling unit only the sound track I I5 overhangs the end of drum I60 and obviously there is ample frictional engagement between the surface of the film strip and the periphery of the drum I60.

As the film advancing assembly is moved from its operative position and drum I60 is retracted from the film handling unit, the reaction roller I03 acts to hold the film strip against the periphery of drum I60 and the action of spring pressed roller 98, tending to stretch the film between rollers 92 and 93, causes the film strip to follow the drum I60 until such time as the film strip reaches a straight line path and the drum I60 is disengaged therefrom. Preferably, and according to the invention the drum I60 of the film advancing assembly is caused to rotate before its engagement with the film strip and continues to rotate until after its disengagement therefrom. The gradual increase and decrease of frictional engagement between the rotating drum I60 and the film strip F1 produces a smooth and even starting and stopping of the film within the film handling units which is desirable from the standpoint of eliminating excessive strains and wear upon the film strip.

Assembly moving means As previously mentioned, the film advancing assembly is moved from an inoperative position into an operative position wherein the film engaging and advancing drum I60 frictionally engages the juxtaposed film strip or film program. According to the invention and as already explained, the film moving assembly is moved into its operative position by means of gravity. Said film advancing assembly is moved from its operative position to its inoperative position by a film moving means which comprises an assembly moving motor I66 mounted upon the channel beam 31 adjacent the fiange I43 of arm I4I of bell crank I31. A reducing gear within housing I61 drives a shaft I68 at a reduced ratio and a crank arm I69 is mounted at one end on said shaft I68 and carries upon its other end a roller I10. As shown particularly in Figs. 4 and 18, said roller I10 engages the lower edge of the flange I43 on the support of the film advancing assembly. When the crank arm I69 is in its lowermost position, see Figs. 3 and 4, the film advancing assembly is in operative position by virtue of gravity. The operative position of the film advancing assembly may be precisely adjusted by means of the set screw I52 on extension I5I. When the assembly moving motor I66 is energized for operation and rotation of crank arm I69 the flange I43, bell crank I31 and the entire film advancing assembly is rotated in a clockwise direction as viewed from Figs. 3 and 18 and the film advancing assembly is moved to its inoperative position and drum I60 is moved out of engagement with the film strip in a film handling unit. The operation of motor I66 may be controlled in a manner to be explained hereinafter whereby the motor is de-energized when the crank arm I69 is moved to its upper position shown in Figs. 18 and 19 and in which the film engaging or sound drum I60 is in inoperative position or in the position shown in Figs. 8 and 18. The reduction gear being irreversible, the weight of the film advancing assembly on roller I10 and crank arm I69 will not move the motor I66 although de-energized. Obviously, the motor I66 may be a reversible motor operative to raise the crank arm I69 in one direction and to lower the crank arm I69 by movement in the opposite direction. Either arrangement of the assembly moving motor I66 will be understood by those skilled in the art.

The optical compensating means Inasmuch as the film strips and film programs are continuously moved within each film handling unit, it is necessary to optically rectify the image projected from the moving film by means of an optical compensator. Such optical compensating means is provided in each of the film handling units and according to the illustrated embodiment is arranged to compensate for the movement of both series of picture images laterally arranged on the film strip.

The optical compensator is best shown in Fig. 13 and comprises an optical flat I1I mounted at each end in circular supports I12 having shaft extensions I13 journaled in ball bearings I14 mounted in rings I15 within the mounting member 12. A barrel type shutter comprises a cylinder I16 fitted into annular recess in circular supports I12 and provided with diametrically opposite apertures I11, see also Fig. 8. Said optical compensating member is arranged in the aperture 16 and enlarged portion 16' thereof of the mounting member 12 and the periphery of the barrel type shutter or cylinder I16 is just beneath the film engaging surfaces of the film guiding track 14 which has film tracks 14 arranged in a known manner to engage the margins and center of the film strip with offset portions therebetween. Such arrangement of the optical compensator within the mounting member 12 not only permits a small spacing between the film and optical fiat I1I but definitely fixes their relative positions since both are in the same integral member. The optical compensator is operatively connected to the film strip in any suitable manner. The operative connection according to the invention has the advantages of simplicity and ruggedness and comprises a spur gear I18 mounted upon one of shaft extensions I13 and within an annular recess I19 in one of rings I15, see Fig. 13. The mounting member 12 is provided with a slot I80, see Figs. 9 and 12, and a pinion gear I8I is mounted by a bushing I82 and set screw I83 upon the shaft 8| carrying the sprockets. Said pinion gear I8I meshes with the spur gear I19 so that rotation of shaft 8|, by movement of a perforated film in engagement with the sprocket teeth 84 or 88 thereon will cause rotation of the spur gear I18 and the optical flat III and shutter I16 of the optical compensator.

Such provision of an opt compensator in each and every film handling unit very simply and conveniently disposes of any problem of framing the images on the film strip F because once the film is threaded through the film handling unit and over sprocket 84 and through the film track I4 over aperture I6 the synchronism between the film and optical compensator will always frame the image properly. Furthermore, the short film path from the sprocket 84 to the aperture I6 eliminates any appreciable effect by shrinkage or stretching of the film after it is threaded in the unit. This arrangement of the optical compensator permits the rotating member or smooth film driving drum I60 to engage the film strip F1 in any relative relation without affecting framing and this is a considerable advantage over any type of mechanical connection which must be disengaged for carriage movement or movement of another film into position and which inherently introduces lost motion and/or lack of synchronism between the driving member on the frame and the film perforations in the film strip of the film handling unit, either or both of which produce an out-of-frame condition.

The sound optical system Basically, the sound reproducing means employed is well known. However, the present invention relates to useful and necessary arrangements of various elements of the optical system for sound reproduction. As usual, the sound optical system comprises a light source, lens for focusing a light beam upon the film sound track and a light-sensitive cell energized according to the characteristics of the sound track.

A lamphousing I84 is mounted by screws I85 upon the arm I36 of the film advancing assembly and encloses a bracket I86 supporting a socket I81 into which an incandescent lamp I 88 is inserted. The front wall of lamphousing I84 is provided with an opening I89. A lens tube I90 is mounted within clamps I9I fastened to arm I36 by screws I92. One end of the lens tube extends into lamphousing I84 adjacent the lamp I88 therein. The sound optical system within lens tube I90 may comprise any suitable condenser and objective assemblies such as a condensing lens I93 and an objective assembly I94. One type of sound optical system which has been found particularly suited for use in the sound reproducing system is disclosed and described in detail in McLeod and Altman U. S. Patent No. 2,146,905, issued February 14, 1939. Since the objective assembly of the sound optics should be very close to the sound track on the film, it is preferred to place the lens tube so that the objective assembly I94 is within the annular recess I62 of the drum I60 and accordingly the lens tube I is provided with a lateral recess I within which a portion of the drum I60 may rotate. While the portion of drum I60 extending into lens tube I90 cuts off some of the light from lamp I88 it has been found that the proximity of the objective assembly I94 to the sound track is more important and the light lost by cut ofi of the drum I 60 does not materially affect the beam directed onto the sound track. The lens tube I90 and objective assembly I94 may be adjusted for proper focusing thereof on the sound track by loosening screws I92, moving lens tube I90 and then tightening screws I92 so that clamps I9I securely hold the lens tube I90 in adjusted position.

The light transmitted through the sound track is collected by an optical conductor having one end adjacent the sound track and the other end adjacent the light-sensitive cell. An internally reflecting bar I96 has a tapered end I91 adjacent the film when moved into its curved path by the drum I60 in operative position. Said bar I96 is mounted within the film handling unit by a holder I98 mounted on the side wall 69 of each film handling unit by screws I99. Said bar I96 is preferably made of Lucite but may be made of any other material capable of internally refiecting the light conducted thereby. The tapered end I91 of said bar I96 is wide enough to extend across both of the sound tracks H3 and H5 on the film strip and is angularly arranged so that the narrow face of tapered end I9"! is substantially parallel to the film F1, The other end of bar I98 is adjacent a photo-electric cell 44 which is mounted in a socket 20I upon the bracket 43, see Fig. 3. Thus, the light directed through either of the sound tracks H3 or H5 is efficiently collected and transmitted to the photoelectric cell 44 as each film handling unit is brought into position for reproduction therein. The remainder of the sound reproducing system comprises the amplifier 3I and loud speaker 30 which are connected to the photo-electric cell 44 in a known manner.

Film operated control means The duration or termination of the film programs is determined by structural variations placed upon the film strip adjacent the conclusion of the film program thereon. Although such film operated means are broadly known, the film operated means according to the present invention has certain features and advantages not found in the prior art and particularly applicable to the provision of laterally adjacent film programs on the film strip.

The film operated projection control means is shown in Figs. 8, 15 and 16 and comprises a block 202 slidably mounted upon a pair of headed studs 203 which are mounted in arm I35 of the film advancing assembly support and a pair of coil springs 204 encircle studs 203 normally to press the supporting block 202 into engagement with said arm I36. A cam 205 extends from block 202 and is arranged to engage a film handling unit and/or to move into the film handling unit according to the relative position of the same and the film advancing assembly. A switch member is mounted upon said block 202 and comprises a stationary contact arm 206 carryin a contact 20! and a spring contact arm 208 also mounted upon block 202 and having a curved end 209 and carrying a contact 2l0.

The film operated means is mounted on arm I36 in any suitable position so that spring arm 208 may engage the edge of the film strip in the unit. Spring arm 208 normally assumes a position to open contacts 201 and 2I0. As the film advancing assembly is moved toward its operative position, the curved end 209 of spring control arm 208 engages the edge of the film and closes contacts 201 and 210 to maintain a holding circuit in a manner later to be described. Contacts 201 and H remain closed until a notch H6 in the unperforated margin of the film strip and adjacent the end of the film program arrives opposite spring control arm 208 and permits it to open in the manner shown in Fig. 16. The supporting block 202 is shown in Fig. 16 in the position for being operated by a film from which the picture series H4 and/or sound track I I5 is being reproduced. When the carriage and film handling units are moved to position a picture series H2 and/or sound tracks H3 for projection and/or reproduction, the relative position of the side wall 69 of the film handling unit and the arm I36 of the film advancing assembly will be that shown in Fig. 15. Upon movement of the film advancing assembly toward the film handling unit the cam 205 engages the edge of side wall 69 and moves the block 202 and switch members thereon laterally and into the position shown in Fig. 15 whereupon the curved end 209 of the spring control arm 208 engages and is closed by the edge of a film strip F from which the picture series H2 and/or sound track H3 is to be reproduced. As before, the contacts 201 and H0 will be closed during movement of the film advancing assembly into operative position and will be opened by a structural variation or notch I IS on the film strip F adjacent the end of the program thereon.

Another film operated means is provided to protect the projector against operation when the film strip is not being moved through the film handling units either because of some film break or because of some failure in the film drive. Such a protective control means comprises, according to the invention, a member responsive only to longitudinal movement of the film and operative when there is no film movement to interrupt projection. The member responsive to film movement comprises a roller 2H connected through gears 2i2 to a. rotating electrical means within a housing 2I3 mounted upon a bracket 2I4 on arm I36 of the film advancing assembly. Specifically, a small generator may be mounted within housing 2 i3 to produce a control current effective to interrupt a projection operating or projection control circuit. Alternatively, a centrifugally operated switch may be placed within housing H3 and adapted when not rotated to interrupt such projection operating projection control circuit. While protective control means responsive to film movement or film breaks are generally known, the location of such control means on a movable film advancing assembly to co-operate with any of several film programs in the manner herein disclosed is novel.

The manner of connecting the film operated control means just described into the control circuits for the purpose mentioned will be explained hereinafter.

The selector mechanism The selector control means is for the purpose of supervising the carriage operating means or carriage movement to position a selected film program in juxtaposition to the optical systems of the projector and/or sound reproducing means. Such a selector control means is responsive in the usual manner to the operation of the push buttons 32 located on the front of the cabinet and according to the invention the selector control means comprises a conductor member having a movement corresponding to carriage movement and for interrupting carriage movement when the carriage and film advancing assembly are in a predetermined relative position. Although the selector control means of the invention is illustrated and described as applied to a multi-program projector, such selector control means is also applicable to control relative movement of any pair of members having a plurality of predetermined positions and one of which is moved by an operating means.

In the illustrated embodiment the selector control means comprises a plurality of contacts 2l5 mounted upon an insulating strip 216 and each corresponding in position to one of the predetermined relative positions of the carriage. and film advancing assembly. The insulating bar 215 ismounted between a pair of lateral supports 2|! which have their ends mounted by bolts 2 [1 upon the tops of end frames 46, see Fig. 4. The contacts 2l5 are each individually composed, as shown in Fig, 8, of a hollow shouldered stem 2I8 extending through strip 2H5 and held in place by a nut 2|9, a contact plunger 220, a spring 22! within the stem and bearing upon the head of plunger 220, and a screw cap 222 bearing upon the other end of spring HI and for attaching a wire 223 to the contact. A pair of direction contacts 224, similar in construction to contacts 215, are mounted at each end of the insulating strip 2|6.

A conductor assembly comprises a rack bar 225 having its teeth meshing with a pinion gear 220 on the shaft I26 of the carriage operating means. A pair of side channels 221 are attached on each side of rack bar 225 and engage a plurality of rollers 228 mounted upon the lateral supports 211 by headed studs 229. An insulating layer 230 is placed upon the top of rack bar 225 and the upper flanges of side channels 221 and in turn supports a conductor bar which has conducting portions 23! and 232 and an intermediate insulating portion 233, see Fig. 5.

The gear connection between the conductor of the selector control means and the carriage operating means may have any suitable ratio but preferably is, as shown, a reduced ratio of the order of two-to-one. The principal requirement of such gear connection is that the conducting portions 23| and 232 and the insulating portion 233 have a movement directly corresponding to the movement of the carriage means and in the case of the present invention said portions have a simple harmonic motion like that of the carriage means, The conducting portions 25 and 232 need only have a total extent equal to the movement corresponding to the carriage movement. However, to permit the use of resiliently operated contact plungers 220 and to overcome the difficulty of making and breaking contact with said portions 23! and 232 and in order to supply a convenient direction control means said conducting portions 23! and 232 have a total length such that the contacts 2l5 and 224 are always in engagement with either conducting portion 23! or conducting portion 232. The direction control contacts 224 are spaced at a distance greater than the movement of the insulating portion 233 and so that one of said contacts 224 always and only engages the conducting portion 23! and the other of said contacts 224 a]- ways and only engages the conducting portion 232. The purpose of this arrangement of the direction control contacts 224 will be better understood in connection with the explanation of the direction control circuits.

Electrical control and operating circuits The motors, relays, switches, lamps, amplifiers, coin-controlled mechanism, selector switches, etc. embodied in the control and operating circuits now to be explained and diagrammatically illustrated in Fig. 20, are of standard form and are commercially available. The present invention relates primarily to the arrangements and corelation of such elements to produce the control and operating functions necessary and desirable to the optimum performance of a multi-program projector.

All of the operating circuits to be mentioned hereinafter are connected directly across a standard source of electrical energy and represented by mains 234 and 235, either or both of which are fed through a fuse 236 and main switch 231. Most of the control circuits are connected across the secondary of a transformer 238 which has a primary winding 239 across supply mains 234 and 235 and which has a secondary winding 240 connected at one end by a wire 24! to main 235 and connected at the other end by a secondary supply main 242 to the control circuits to be enumerated.

The coin-controlled mechanism comprises the slot 33 in the front of the cabinet and a pair of contacts 243 arranged to be closed upon passage of a coin through said coin slot 33. One of contacts 243 is connected to wire 242 and the other of contacts 243 is connected through a switch member H1 and wire 245 to one side of a relay coil A which is adapted when energized to operate switch arms A1, A2, A3, and A4, switch arms A1 and A2 being normally open and closed by energization of coil A, while switch arms A: and A4 are normally closed and are opened by energization of relay coil A. The other side of relay coil A is connected by a wire 246 to a normally closed limit switch LS1 and by a wire 241 to the supply main 235. As a result, insertion of a coin 248 to close contacts 243 completes the circuit through relay coil A to energize the same, to close switches A1 and A2 and to open switches A: and A4.

A holding circuit for the relay A is established by the closing of switch A1 and extends from the secondary main 242 through a wire 249, through switch A1, through a wire 250, through relay coil A, through wire 245, through limit switch LS1 and wire 241 to the supply main 235. The switch LS1 may be shunted by an auxiliary circult including a film operated switch FS including a fixed contact 201 and spring control arm 208 shown in Figs. 15 and 16 and said shunt circult includes a wire 25l connected between wire 246 and contact 201 and a wire 252 connected between switch arm 208 and wire 241. The limit switch LS1 has a plunger 253 adapted to be operated by a stud 254 and which is mounted in a bracket 255 on the fiange I43 of the film advancing assembly. For convenience, it may be necessary to mount a leaf spring 256 upon limit switch LS1 in contact with said plunger 253. Said stud 254 is so adjusted and said limit switch LS1 is so located upon the projector frame that the normally closed switch LS1 is opened shortly before the film advancing assembly is moved into the operative position of the film advancing assembly and drum 160 shown in Figs. 3 and 14. The film switch FS and its arms 206 and 208 are so mounted and located upon the arm 138 of the film advancing assembly that the contacts 201 and 2K! are closed by engagement of the spring control arm 208 with the edge of the film program somewhat before the limit switch LS1 is open. This closing of the film switch FS before opening of the limit switch LS1 during inward movement of the film advancing assembly is indicated by the diagram entitled Holding circuit of Fig. 21. Under normal operating conditions the holding circuit will be maintained until the film switch FS is opened by the structural variation on the film strip or until a notch H6 in the margin of the film strip permits spring control arm 208 to move its contact away from the stationary contact 2). However, if for any reason there should be no film in position for engagement by the spring control arm 208 of film switch PS the film switch would remain open and upon opening of limit switch LS1 the holding circuit is interrupted and the inward movement of the film advancing assembly will be stopped and reversed in a manner to be explained. For obvious reasons the film strip F, after opening of the film switch FS, continues to move until the notch IIB passes its point of engagement with the spring control arm 208 and the film switch FS is closed again, having been opened only for a short interval. Nevertheless, the interruption of the holding circuit has de-energized relay coil A and permitted switch A1 to open so that reclosing of film switch FS after passage of the notch H6 does not reestablish the holding circuit. Subsequently, the limit switch LS1 is closed during outward movement of the film advancing assembly and shortly thereafter the film switch FS is opened by disengagement of the spring control arm 208 from the edge of the juxtaposed film strip. These sequences of operations of film switch FS and limit switch LS1 are indicated in the righthand portion of the diagram entitled "Holding circuit in Fi 21.

The selector control means includes the selector contacts N5, the direction control contacts 224, the conducting portions 23 l and 232 and the insulating portion 233 already described and also a selector control circuit now to be explained. The selector switches ar of known design and there is a selector switch corresponding to each predetermined relative position of the two movable members or for each film program on the carriage. Such selector switches eachcomprise a switch arm 251 operated by the corresponding push button 32 available at the front of the cabinet and normally engaging a back c0ntact 258 but moved by operation of push button 32 into engagement with a front contact 259, see Fig. 20. Each back contact 258 is connected by a wire 250 to the switch arm 251 of the adjacent selector switch and each front contact 259 is connected by a wire 28l to the corresponding selector contact 2|5. The selector switches and push buttons are of a conventional design in which the push button and corresponding selector switch remain in operative position until another push button is operated or until an "all release button is operated to clear all of the push buttons 32 and return all of the selector switches to their normal position. Also, the selector switches are connected in series through switch arms 251 and back contacts 258 until one of switch arms 251 is operated by the corresponding push button 32 and such operated switch arm 251 is connected by a corresponding wire 261 to a corresponding selector contact 2l5 and such operation of a switch A1 which is closed by insertion of a coin,

through a wire 262, through a relay switch D2, through a wire 263, through switch arms 251, back contacts 258 and wires 260 of the selector switches, through one of wires 26I and one of selector contacts 2I5 and then through either of a pair of direction control circuits. One of said direction control circuits comprises a wire 264 connected to one of the direction control'contacts 224, a relay coil B and a wire 265 connected to the supply main 235. The other direction control circuit includes a wire 266 connected to the other direction control contact 224 to a relay coil C and a wire 261 to the supply main 235. Assuming that the conductor bar of the selector control means is in the position illustrated in Fig. 20 or that the number 1 film program, counted from the left of the film carriage, had just been reproduced and that push button 32 corresponding to the number 4 film program has been manually operated, then the selector control circuit extends as previously traced to the fourth selector contact 2I5 through conducting portion 232 of the selector conductor bar and through the direction control circuit including wire 266, relay coil C and wire 261. The other direction control circuit is not energized because the insulating portion 233 is between the energized contact and the right-hand direction control contact 224. However, if the selector contact 2I5 corresponding to the numbe 8 program had been energized then the selector control circuit would extend through the direction control circuit comprising wire 264, relay coil B and wire 265. The relays including coils B and C are direct acting relays and each includes a normally open and a normally closed switch, moved to opposite positions by energization of the coils B or C.

A selector operating circuit is responsive to energization of the selector control circuit and includes the indexing motor I3I of the permanent magnet pole type and which is operated in opposite directions for corresponding movement or indexing of the carriage. Such selector operating circuit comprises a common wire 268 extending from supply main 234 through a switch B1 to one side of indexing motor I3I which has its other side connected by a common wire 269 to the supply main 235. Energization of the indexing motor I3I through said switch B1 operates the same to move indexing arm I25 in a clockwise direction and thereby moving the carriage, the film handling units, the conducting portions 23I' and 232 and insulating portion 233 to the right as viewed in Figs. 3, 5, and 20. The selector operating circuit also includes a branch circuit comprising a wire 216, switch and a wire 2' connected to indexing motor I3| to cause its operation for counter-clockwise rotation of the indexing arm I25 and movement of the carriage and conductor bars to the left as viewed from Figs. 4, 5 and 20. By reason of the insulating portion 233 relay coil B and relay coil C can not be energized simultaneously so that switches B1 and C1 can not be closed at the same time. Consequently, energization of conducting portion 23I or 232 by the operation of a selector switch connected to a selector contact 2I5 in engagement with either of said portions determines the branch of the selector operating circuit to be energized and will always cause rotation of the indexing motor I3I in such a direction as to move the insulating portion '233 of the selector bar toward the selector contact 2I5 connected to a manually operated selector switch. Referring to the diagram of Fig. 21 entitled Selector operating circuit it will be noted that the selector operating circuit is closed through switch .131 or 0; upon selection of a film program and upon the insertion of a coin and energization of relay coil A and will be interrupted by the engagement of insulating portion 233 with the selector contact 2I5 corresponding to the selected film program as soon as that program is moved into juxtaposition with respect to the optical system of the projector.

An assembly control circuit is provided to supervise the operation of the assembly moving motor I66 for inward and outward movement of the film advancing assembly. Said assembly control circuit is also arranged according to the invention so that the aforementioned selector control circuit has preference thereover and so that the selector control and assembly control circuits can not be simultaneously completed. The assembly control circuit extends from secondary main 242 through a wire 212, through switch A2, through a wire 213, through switch B2, through a wire 214, through switch 02, through wire 215, through relay coil D and through a wire 216 to the supply main 235. The relay including the coil D is of a well known time delayed action type and comprises a normally opened switch D1 and normally closed switch D2, which switches are not operated from their normal positions until an interval, approximately one-half second, following energization of the relay coil D. Thus, when relay coil A is energized, switch A1 and A: are closed at the same time but the delayed action interval insures that relay coil B or relay coil C are energized to open either switch B2 or switch C: before relay coil D has been energized to open the switch D2 in the selector control circuit. During the selection cycle the assembly control circuit is locked out by the opening of either switch B: or switch C2. At the completion of the selection cycle switches B2 and C: are both closed and relay coil D is energized so that after the aforementioned delayed action interval switch D2 is opened to interrupt the selector control circuit and the switch D1 is closed for a purpose next to be described. Said assembly control circuit is only operative during the in" movement of the film advancing assembly because said assembly control circuit is interrupted by opening of the switch A: upon de-energization of coil A after completion of the film program. The details of the function of the assembly control circuit are also illustrated in the diagram of Fig. 21.

Two assembly operating circuits are provided, one for energizing the assembly moving motor I66 to permit movement of the film advancing assembly and drum I60 toward and into operative position and the other for energizing the assembly moving motor I66 to move the film advancin sembly and drum I60 from operative position toward and into the extreme inoperativ position shown in Figs. 8 and 16. The first mentioned assembly operating circuit includes a limit switch LS: which is operated to interrupt said circuit upon movement of the film advancing assembly to it final operative position or the position shown in Figs. 3 and 14. Preferably, said limit switch LS: also completes a projection control circuit simultaneously with the opening of the assembly operating circuit in. Consequently, limit switch LS: is preferably a single pole double throw switch including a plunger 211 and a switch arm 218 normally engaging the contact 219 but movable into engagement with a contact 280. Said 1 limit switch LS2, see Figs. 4 and 18, is mounted on the frame in a position so that an adjustable stud 28I mounted in a bracket 282 on flange I43 of the film advancing assembly support engages said plunger 211 to move the switch arm 218 from engagement with contact 219 and into engagement with contact 280 just as the film advancing assembly and drum I60 thereof are moved into the final operative position. The assemblyoperating circuit comprises a wire 283 connected to switch arm 218 of limit switch LS: and extends through contact 219, through a wire 284, through switch D1, through a wire 285, through assembly moving motor I68 and through a wire 286 to the other supply main 235. Completion of said assembly operating circuit energizes the motor I66 for rotation so as to move the crank arm I69 from the position shown in Figs. 18 and 19 to the position shown in Figs. 3 and 4. As previously mentioned, the center of gravity of the film advancing assembly is such that the flange I43 thereof follows the roller I10 on crank arm I89 and as a result the operation of motor I66 permits movement of the drum I60 into its final operative position. Just as the film advancing assembl and drum I60 are moved to said final operative position, the stud 28I engages plunger 211 to move switch arm 218 out of engagement with contact 219 to open said assembly operating circuit "in and to deenergize the assembly moving motor I66. As shown in the diagram of Fig. 21 entitled Assembly operating circuit in the contact 219 and switch arm 218 of limit switch LS2 remain open during the picture and sound reproduction at the conclusion of which relay A is de-energized to open the assembly control circuit and in turn de-energizing coil D to open switch D1 so that the assembly operating circuit "in can not again be completed until switch D1 is closed by re-energization of the relay coil A and closing of the switch A2.

A also previously mentioned, the film engaging drum I60 is rotating during the in" and out movement of the film advancing assembl and during picture projection and sound reproduction. The film drive motor I63 as already explained drives the drum I60. The energization and deenergization of said film drive motor I83 is determined by a film advance operating circuit including a wire 281 connected between supply main 234 and one side of a normally open limit switch LS4, includes a wire 288 connected between the other side of limit switch LS4 and film drive motor I63 and a wire 289 connected between the other side of film drive motor I63 and supply main 235. Said switch LS4 has a plunger 290 and may have a leaf spring 29I extending thereover and into the path of a stud 292 mounted upon a bracket 293 on the fiange I43 of the film advancing assembly support. Said switch LS4 is mounted upon the frame of the projector and is relatively arranged with respect to stud 292 so as to be closed by engagement of the stud 292 with leaf spring 29I during the inward movement of the film advancing assembly and before the drum I60 engages the film strip F1 between the rollers 92 and 93 of the film handling unit. Conversely, this arrangement of a switch LS4 and stud 292 opens the circuit to film drive motor I 63 after the drum I80 has been moved out of engagement with the film strip F1. This rotation of the drum I60 before, during and after its engagement with the film strip insures the aforementioned smooth and even starting and stopping of film movement. The relative energization of said film advancing operating circuit is illustrated in Fig, 21.

Decorative lights 294 are disposed at suitable locations on or within the cabinet so as to illuminate the same and/or the screen 25 thereof to make the projector attractive while inoperative. The decorative lighting circuit extends from the supply main 234 through a wire 295, through switch As, through a wire 296, through said decorative lights 294, and through a wire 291 to the other supply main 235. Since switch A: is normally closed the decorative lights will be on when the projector is not operating and the lighting circuit will be interrupted to extinguish said lights 294 upon the insertion of a coin 248 and energization of the relay coil A.

A projection control circuit is preferably arranged so that the projection lamp 40, blower motor 42 and exciter lamp I88 are energized only during the projection and sound reproduction portion of the operating cycle of the projector. This is accomplished by a projection cycle circuit preferably energized alternatively with opening of the assembly control circuit in and including a wire 298 connected to contact 280 of limit switch LS2, a relay coil E, a wire 299, a normally open switch F1 and a wire 300 connected to the supply main 235. Said projection control circuit is preferably provided with a protective control means responsive only to movement of the selected or juxtaposed film strip and for maintaining the projection control circuit only when a selected film strip is in position and is moving. In the illustrated embodiment such protective control means comprises a small generator G to be mounted within the housing 2I3 on arm I36 of the film advancing assembly support. Said generator G is connected by wires 30I and 302 to a relay coil F which when energized holds the normally open switch F1 in closed position. Alternatively, and within the scope of the invention any other means responsive only to film movement may be provided to maintain the projection control circuit closed and such means may be centrifugally operated means responsive only to film movement and including or operatively connected to switch F1 which will be closed to maintain the projection control circuit only during the presence of a moving film in the film handling unit. As shown in the diagram of Fig. 21 entitled Projection control circuit" the closing of switch arm 218 and contact 280 completes the same and may be interrupted during the picture-sound reproduction portion of the operating cycle if the film strip stops or breaks. Finally, the projection control circuit is open when the film advancing assembly is moved out of its final operative position and when the switch arm 218 of limit switch LS2 moves out of engagement with contact 280. The relative energization of the protective control circuit is also shown in Fig. 21 and said protective control circuit is prepared or completed before completion of the projection control circuit by engagement of the roller 2| I with the film strip prior to commencement of the picturesound reproduction and roller 2 continues to rotate under normal conditions to maintain switch F1 closed until after the projection control circuit has been opened by disengagement of switch arm 218 and contact 280 and switch LS2.

One or more projection operating circuits are provided and are completed by normally opened switches, such as switch E1 and E2, which are closed by energization of the relay coil E in the projection control circuit. One such projection operating circuit includes a wire 303 connected to supply main 234, switch E2, wire 304, projec- 

